Inhalation-exhalation regulator system with suction control



Dec. 2, 1969 J. B. GARRISON I 3,481,333

INHALATION-EXHALATION REGULATOR SYSTEM WITH SUCTION CONTROL Filed March31, 1966 I l l llll I 7;?

5% as as L 76 INVENTOR. SUCT'ON 75572 B. Garrz'sarz ATTORNEYS.

United States Patent 3,481,333 INHALATION-EXHALATION REGULATOR SYSTEMWITH SUCTION CONTROL John B. Garrison, Clarence, N.Y., assignor, bymesne assignments, to Automatic Sprinkler Corporation of America,Cleveland, Ohio, a corporation of Ohio Filed Mar. 31, 1966, Ser. No.539,063 Int. Cl. A62b 7/04, 18/04; A61h 31/00 US. Cl. 128142.2 ClaimsABSTRACT OF THE DISCLOSURE A control chamber with a movable wall has afluid inlet communicating with a fluid outlet from a breathing mask orother life support system for movement of the wall upon fluid flow intothe chamber from the system, and a fluid outlet communicating with asource of suction. A normally closed valve controlling fluid flowthrough the chamber outlet is opened by such wall movement to place thechamber in communication with the suction source. A bleed passagecommunicating with the suction source exhausts fluid from within a hoodcovering the head of a wearer, and a bleed control valve operates inconjunction with the chamber outlet valve to enable opening of thelatter against high suction pressure from the source with a minimumexhalation elfort.

This invention relates generally to the control art, and morespecifically to a new and useful suction control for life supportsystems.

When a person must subsist in an atmosphere which is dangerous orincapable of supporting human life, he is equipped with a life supportsystem comprising, for example, a breathing mask supplied with oxygenfrom either a fixed or portable source, through a demand regulator.Under ordinary circumstances, the exhalation from the life supportsystem can be exhausted to the ambient atmosphere.

However, under some circumstances it is essential that the surroundingatmosphere not be contaminated with exhalation or any other gas from thelife support system. Pending application Ser. No. 409,065, filed Nov. 5,1964, now US. Patent 3,348,538 by Howard A. Benzel and assigned to theassignee of this application discloses a suction control arrangement forreceiving exhalation from a breathing mask, pressure suit or the like,and removing it under pressure in a manner avoiding contamination of thesurrounding atmosphere.

It is desirable to obtain a large volume of flow from the suctioncontrol regulator, and thereby literally take away the exhalation.However, it also is desirable to keep the weight of the suction line toa minimum and thereby reduce the total weight which must be carriedabout by the user. This poses a problem because a relatively highsuction pressure must be provided to obtain a large flow rate through asmall diameter line, and this in turn requires a relatively largecracking force to open the outlet valve from the suction regulator. Thisis undesirable, because of the expiration eflort needed to develop sucha force.

A primary object of this invention is to provide a suction controlarrangement for life support systems enabling the utilization of a highpressure suction source and opening to the source with a minimum ofeffort.

The foregoing and other objects, advantages and characterizing featuresof this invention will become clearly apparent from the ensuing detaileddescription of an illustrative embodiment thereof, reference being madeto the accompanying drawing depicting the same wherein like "ice fullface breathing mask supplied with a breathing fluid from suitable source(not shown) via a breathing hose 2 and a conventional demand regulator3. Regulator 3 can be of any desired type, such as that set forth inUnited States Patent 3,145,721 and is mounted either on mask 1 or on thewearers suit and connected to mask 1 by a suitable hose, eitherarrangement being well known in the art. Also, the breathing fluid canbe supplied from either a fixed source, or a portable source such as acylinder of compressed air or oxygen, not shown, carried on the back bymeans including a harness 4, both arrangements being well known in theart and requiring no elaboration here.

The life support system can also include a communications system,including a microphone 5 mounted in the oro-nasal cavity 6 of the maskand connected via lead 7 to a connector 8 and service line 9.

A suction control is provided in the form of a regulator 10 having aninlet conduit 11 connected to face mask 1 for receiving exhalation orother gas therefrom. A oneway check valve 12 permitting fluid flow onlyin the direction of arrow A is positioned in conduit 11, valve 12 beingof the flapper type. Regulator 10 has an outlet fitting 13 connected toa bleed valve housing 14 communicating therethrough and via suction line15 with a source of suction 16. Suction source 16 can be positionedeither nearby or a substantial distance away and can be in another room.

Regulator 10 can be identical with the regulator 6 of the aforesaidapplication Ser. No. 409,065, and can have a vacuum break flapper typecheck valve to relieve the vacuum if the regulator should stick in openposition, as shown therein. In the illustrated embodiment, regulator 10comprises a housing including a generally cup-shaped body 17 and a cover18 held together by a generally U-shaped clamping ring 19. A movablewall, herein shown as a resiliently flexible diaphragm 20 is suspendedacross the open end of body 17, being clamped between body 17 and cover18 by the clamping ring 19.

The outlet fitting 13 provides a fluid outlet passage 21 controlled by atilt valve having a body 22 of any suitable construction. Body 22engages a valve seat 23 around the outlet passage 21, and a valve stem24 extends from valve body 22 into the chamber 25 provided in housing 17by diaphragm 20. Stem 24 extends generally parallel to diaphragm 20through an elongated opening or slot 26 in a connecting link member 27carried by a back up plate 28 secured to diaphragm 20 for movementtherewith. Connecting link 27 can be integral with and of the diaphragmmaterial.

Inlet conduit 11 communicates with chamber 25 of the control 10, andstem 24 normally engages the outer end of slot 26, this being the upperend of the slot as viewed in FIG. 2, whereby movement of diaphragm 20toward cover 18, in the direction enlarging chamber 25, will tilt stem24 downwardly, pivoting valve body 22 on valve seat 23 at the lowerportion thereof as seen in FIG. 2, thereby opening fluid outlet passage21 and placing the suction source 16 in communication with chamber 25.Movement of diaphragm 20 in a direction reducing the size of chamber 25will not tilt stem 24, because of the lost motion connection 3 providedby slot 26 and interference of the nearly rigid link 27 with the bottomof housing 17.

A bifurcated arm 29 at the valve body end of a spring bracket 30 has avertical slot through which stem 24 extends and in which it can tiltvertically, in the plane of the pap as viewed in FIG. 2, withoutinterference. However, undue lateral movement of stem 24 is prevented byarm 29. A helical spring 31 encircles stem 24 between arm 29 and valvebody 22, bearing at one end against the latter. At its opposite end,spring 31 bears against arm 29, being held against lateral shifting byflanges 32 extending from the opposite sides of the bifurcated arm 29 atgenerally a right angle thereto. Multiple protrusions 33 projectradially from body 22 for engagement with the wall 34 of fitting 13, tocenter valve 22 on its seat.

The chamber between cover 18 and diaphragm 20 is at ambient atmosphericpressure, being open to the surrounding atmosphere through severalopenings 35.

It will be noted from FIG. 1 that a transparent hood 36 of plasticmaterial is provided, the hood covering the head and having an apron 37extending downwardly to also cover the shoulders and upper body of thewearer. Hood 36 encloses breathing mask 1, regulators 3 and 10, and theassociated equipment including the bleed housing 14, and provides aspace about this equipment in which any leakage of air from the lifesupport system will be trapped. For example, if the mask 1 does not havea fluid tight seal with the head of the wearer, some breathing fluid mayescape. This would be trapped within hood 36. To remove such trappedfluid, there is provided a bleed connection into the suction line 15,and it is a particular feature of this invention that the bleedconnection is provided with a control valve operating in conjunctionwith valve 22 to cause the latter to open against a high suctionpressure from source 16, with a minimum of exhalation effort. This isaccomplished as follows.

Referring now to FIG. 2, there is provided a bleed passage 38 into thehousing 14, the passage 38 communicating with the interior of hood 36for fluid flow in the direction of arrow B. Passage 38 is smaller inarea than the outlet passage 21 from chamber 25, and is provided with avalve seat 39 adapted for engagement by a bleed valve body 40. A stem 41extends from body 40 through passage 38 and has a head 42. A helicalspring 43 extends between a recessed seat 44 in the wall of housing 14and the head 42, encircling stem 41 and biasing the body 40 into closedposition against seat 39. An open ended, hood-like skirt 45 encirclesspring 43 and the bleed valve stem 41 and head 42, to protect the same.

Spring 43 is arranged so that when valve 22 is closed, valve 40 isopened by the suction influence from source 16. This opens the interiorof hood 36 to suction source 16, for exhausting trapped fluid fromwithin hood 36. In addition, it will draw fluid from beneath hood 36,and thereby utilize the ambient atmosphere to ventilate the interior ofthe hood, for the comfort of the wearer. In other words, it will notonly draw fluid from within the hood, but in doing so it will causefluid to leak under the hood from the exterior thereof, into the hoodand through the suction line 15. To prevent collapsing of the hood aboutthe wearer, should such ventilating leakage somehow be pre vented, thereare provided a pair of one way, inlet check valves 47 of the flappertype, and of suflicient stiffness to open only upon a predeterminednegative pressure, whereby normally they will be closed but will openshould that be the only way for ambient atmosphere to enter the hood.

It is a particular feature of my invention that fluid flow through thebleed passage reduces the suction force which must be overcome to openvalve 22. When valve 22 is cracked open, the suction pressure is furtherreduced, because of fluid flow through passage 21, whereupon valve 40closes under the influence of spring 43. For example, with a suctionpressure equal to 29 inches of mercury, spring 43 can be arranged toclose valve 40 when the effective suction pressure thereon drops belowinches of mercury.

This means that with fluid flow through bleed passage 38, valve 22 mustopen against an effective suction force of only 15 inches of mercury, orapproximately half the full suction pressure. Upon cracking valve 22open, the effective suction pressure on valves 40 and 22 drops, causingvalve 40 to close whereby the full suction force is applied to the fluidin chamber 25. Once valve 22 is cracked open, the application of fullsuction pressure thereon does not impede further opening movement of thevalve, because the maximum effort is required at the initial opening orcracking of the valve.

Therefore, a high suction force can be utilized with my invention, witha modest effort required to crack open the valve, and with the fullsuction effect being immediately applied to the regulator 10 because thebleed passage is closed whenever the chamber 25 is opened to the suctionsource 16. Also, closing of the bleed passage 38 whenever chamber 25 isopened ensures that no gas from chamber 25 will escape through the bleedpassage 38, thereby precluding possible contamination of the ambientatmosphere by a malfunction in this aspect of the system.

It will be appreciated that the demand regulator 3 of the breathingfluid supply can have a check valve arrangement between it and the mask1 corresponding to check valve 12 but opening in the opposite direction,whereby all exhalation will be delivered to regulator 10, and allinhalation will be from regulator 3.

Accordingly, it is seen that my invention fully accomplishes itsintended objects. While I have disclosed and described in detail onlyone embodiment, that has been done by way of illustration only withoutthought of limitation.

Having fully disclosed and completely described my invention, and itsmode of operation, what I claim as new is:

1. In combination with a life support system having a fluid outlet, asource of suction, and a control including a chamber having a movablewall, a fluid inlet to said chamber communicating with said systemoutlet for movement of said wall upon fluid flow into said chamber fromsaid system, a fluid outlet from said chamber communicating with saidsource of suction through a suction line, normally closed chamber valvemeans controlling fluid flow through said chamber outlet, meansconnecting said chamber valve means to said movable wall for placingsaid chamber in communication with said source of suction upon suchmovement of said wall, a bleed passage into said suction line, bleedvalve means controlling fluid flow through said passage and operative toinfluence the effort required to open said chamber valve means, andmeans biasing said bleed valve means to close said bleed passage, saidbleed valve biasing means being arranged to close said bleed valve meansagainst the suction influence thereon of said source when said influencefalls below a first pressure level, said source being operative to exerta suction influence on said bleed and chamber valve means at a secondpressure level substantially above said first level, said bleed valvemeans opening against said bleed valve biasing means when said suctioninfluence is above said first level and said chamber means is closed,said chamber valve means being arranged to reduce the suction influenceon said bleed valve means below said first level upon opening of saidchamber valve means and said bleed valve biasing means coacting withsaid chamber valve means to maintain said bleed valve means closedwhenever said chamber valve means is open, whereby the suction forcewhich must be overcome to open said chamber valve means is reduced tosaid first level and the full suction effect is applied to said chamberupon opening said chamber valve means.

2. The combination of claim 1, wherein said life support system includesa breathing mask connected to said fluid inlet, together with a hood ofgas impermeable material adapted to enclose the head of a person wearingsaid mask, said bleed passage opening into said hood for withdrawingfluid from within said hood.

3. The combination of claim 2, wherein said hood is open at the lowerend thereof, whereby said hood is ventilated by said suction source whensaid chamber outlet is closed.

4. The combination of claim 3, wherein said hood has a relief passagethrough a wall thereof, together with check valve means normally closingsaid relief passage, said check valve means opening inwardly under apredetermined suction influence to admit fluid into said hood andthereby prevent collapsing thereof against the wearer.

5. The combination of claim 2, wherein said life support system hasmeans including a demand regulator for supplying breathing fluid to saidmask.

6. The combination of claim 1, wherein said life support system includesmeans for supplying fluid under positive pressure thereto.

7. The combination of claim 1, wherein said movable wall comprises a,flexible diaphragm, and said connecting means comprises an actuatingstem extending from said chamber valve means, a spring encircling saidstem and urging said chamber valve means into a position closing saidchamber outlet, and lost-motion means connecting said actuating stem tosaid diaphragm for tilting the former to open said chamber outlet uponmovement of said diaphragm in a direction enlarging said chamber.

8. The combination of claim 7, wherein said bleed valve biasing meanscomprises a spring.

9. The combination of claim 1, said bleed passage being smaller in areathan said fluid outlet from said chamber.

10. In combination with a life support system having a fluid outlet, asource of suction, and a control including a chamber having a movablewall, a fluid inlet to said chamber communicating with said systemoutlet for movement of said wall upon fluid flow into said chamber fromsaid system, a fluid outlet from said chamber communicaing with saidsource of suction through a suction line, chamber valve meanscontrolling fluid flow through said chamber outlet, means connectingsaid chamber valve means to said movable wall for placing said chamberin communication with said source of suction upon such movement of saidwall, a bleed passage into said suction line, bleed valve meanscontrolling fluid flow through said passage and operative to influencethe effort required to open said chamber valve means, said bleed valvemeans moving to open said bleed passage in response to the suctioninfluence of said source of suction, and means biasing said bleed valvemeans to close said bleed passage, together with means providing anenclosure about a portion of said life support system, said bleedpassage placing said suction line in communication with the interior ofsaid enclosure exteriorly of said life support system.

References Cited UNITED STATES PATENTS 1,169,995 2/1916 Prindle128-142.3 3,078,846 2/1963 Nevelli et a1. 128--142.2 3,348,538 10/1967Benzel l28142 WILLIAM E. KAMM, Primary Examiner US. Cl. X.R. 128142.7

